Arc-lamp.



No. 876,945. PATENTED JAN. 21, 1908.

G. W. GRAVBNS. ARC LAMP.

APPLICATION FILED SBPT.16,1904.

2 SHEETSSHEET 1.

- Schenectady,

UNITED STATES PATENT OFFICE.

GEORGE W. CRAVENS, OF SOHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

, ARC-LAMP.

Specification of Letters Patent.

Patented Jan. 21, 1908.

Application filed September 16, 1904. Serial N0- 224.660.-

To all whom it may concern;

Be it known that I, GEORGE W. CRAvENs, a citizen of the United States, residing at county of Schenectady, State of New Yor have invented certain new and useful Improvements in Arc-Lamps, of which the following is a specification.

My present invention relates to are lamps, and more particularly to that ty e of arc lamps in which a magnet is emp oyed for deflecting the arc.

. In the arc lamp which I have hereinafter shown and described in detail, a-pair of electrodes are employed which are supported in holders moving toward and away from each other in the feeding operation of the lamp. The electrodes, the ends of which converge toward each other, are inclined to between the arc and the line of movement of the holders and the arcing ends ofthe electrodes are ordinarily arranged in the same horizontal plane; As

the electrodes are consumed tion of the lamp, line of movement of the holders.

in the opera- In order to get the best results from a lamp of this character, I have found it desirable to employ a'magnet to deflect the are between the electrodes and to change its form from an archhaving its middle portion the highest, to a form in which the arc is substantially horizontal or is even bowed downwardly. To preserve unchanged the pro er relation the magnet have connected the latter to the feeding mechanism of the lamp in such manner that the position of the magnet is automatically changed to compensate for the change in the position of the arc produced by thedecrease in length of the electrodes as they waste away.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of my invention, however, reference may be had to the drawings and descriptive matter in which I have illustrated one of the many forms in which my invention may be embodied.

Of the drawings, Figure 1 is anel'evation with parts broken'away and in section of an arc lamp made in accordance with my invention; Fig. 2 is an elevation taken at right an gles to Fig. 1 showing the deflecting magnet and a portion of one electrode; Fig. 3 is a diagram of the circuit connections of the lamp the arc approaches the shown in Fig. 1; and Fig. 4 is a perspective view showing a modified detail of construction.

Referring to the drawings, 1 re resents the cap or hood of the lamp. A p atform 2 is connected to the cap 1 by suitable bolts or posts 3. Guides 4 formed on the upper side of carriages or members 5, slide in slots 6 formed for the urpose in the platform 2. Rollers 7 or the li e, connected to the guide 4, rest against the upper surface of the p atform '2 and support the weight of the carriages 5. The carriages 5 are formed on their under side with sockets in which the electrodes 8 of the lamp are held by clamping screws 9.

The sockets are so shaped that the electrodes five degrees, with their lower ends converging I toward one another. v

A tubular member 10, sliding on a guiderod 11 carried by the cap 1, passes transversely through the platform 2 midway between the carriages 5. The lower end of the member 10 carries a U-shaped magnet 12 which is arranged to straddle the are formed between the ends of the electrodes. The magnet 12 may be a permanentmagnet or it may be an electro magnet energized in any suitable manner.

The member 10 is surrounded by the yoke member of a clutch 15. The pawl of the clutch 15 is connected to the under side of a U-shaped armature 16, thelegs of which are acted upon by a pair of solenoid coils 17 carried upon the cap member 1 in a suitable manner. A dash pot 16 forms a means for limiting the rapidity of the downward movement of the core 16. A stop 18 carried by one of the posts 3 normally su ports the yoke of the clutch member 15 as sliown in Fig. 1. In this position of the posts the member 10 is not locked to the clutch 15.

Some distance above the yoke of the clutch member 15, the ,mer'nber 10 is surrounded by the yoke member 19 of a clutch 20. The pivoted pawl 21 of the clutch 20 .is formed with an aperture in it through which the post 3 passes, thus preventing angular displacement of the pawl. The outerend of the pawl 21 is normally held elevated by means of a helical s ring 22 one end of which is connected to tile pawl and the other 'end of which is connected to the cap 1 thus normally locking the clutch to the member 10. v Stops 23 and 24, placed above of the slots 27 formed in the bifurcated inner. Each guide 4 carries arms of the levers 26. I a pin 30 which engages in the slot 27 formed in the outer arm of the corresponding lever 26. A voltage coilcarried by the cap 1 is provided with a pivoted armature 36. Gravity normallyholds the armature 36 in such position that a contact 37 carried by it is out of engagement with a contact 38 carried bythe coil 35. When the coil 35 is energized -;in the manner hereinafter discribed, however, the attraction of the armature 36 by the coil 35 causes the contact 37 to be moved 25 into engagement with the contact 38.

- A cutout device 40 carried by theplat.- form 2 comprises a U-shaped core 41- having a'coil 42 placed on one leg. An armature in the form of a bar 43 is pivoted to the leg of the core 41, on which the winding is placed. One end of the armature 43 carries a contact 44. The contact 44 normally rests in engagement with a stationary contact 45 when the coil 42 is unenergized. When the coil 42 is energized, however, the armature is tilted so as to separate the contacts 44 and 45.

A resistance conductor 47 is wound about a support 48 connected to the platform 2 and cap 1. I

A casing 50 formed of sheet metal in the usual manner, surrounds the lam mechanism locked between the cap 1 an platform 2. A hood or extension 51 secured to the lower end of the casing 50 is provided with means such as screws 52 for supporting a transparent or translucent globe 53 which incloses the electrodes 8 and protects the are extending between their lower ends.

Referring particularly to the diagram: shownin Fig:-3. and 61 (also shown in Fig. 1) represen the lamp terminals. A conductor 62 connects the terminal 61 with one of the electrodes ofthe lamp. The other electrode of the lamp is connected to one terminal of thewinding 42 of the cutout device by a conductor 63; The other terminal of the cutout device is connected to one terminal of the resistance conductor 47 by a lconductor 64. The other terminal of the resistance conductor 47 is connected to the lamp terminal 60. One terminal of the coils 17 which are in series with each other, is

- connected to the conductor 62 by a conductor 65; The other terminal of the coils 6'5.

17 is connected to the'contact 44 by a conductor '66. The contact 45 is connected to the conductor 64 by a conductor 67. One terminal of the coil 35 is connected to the lamp terminal 6 1 and the other terminal of the -coil 35 is connected to the conductor 64. The contact 38 is connected to the conductor 63 by a conductor 68. The contact 37 is connected to the conductor 64 by a conductor 69.

' The out-of-servicecondition of the lamp is. that represented in the drawings. As soon as the lamp terminals 60 and 61 are connectwill begin to flow. between the terminals 61 and 60 through a circuit including part of conductor 62, the windings of the coils 17, contacts 44 and 45, conductor 67, part of conductor 64 and resistance 47. The assage of this current through the-coils 17 1 cause them to be energized and attract the core of armature 16. The upward movement of the clutch 15 to first grip and then raise the mem-' ber 10. As the member 10 is raised, the oscillation of the bell-crank levers 26 thereby produced will cause the carriages 5 to move toward each other until-the converging ends of the electrodes 8 meet. As soon as the converging ends of the electrodes 8 meet, current will begin to flow between the electrodes, through a circuit including conductor 62,

coil 42, conductor 64, and resistance conductor 47. The passage of current'through the coil 42 will cause the armature 43 to be moved in such a manner as to separate the member 10 bemoved downward by the action of gravity upon it and the magnet 12 oarriedby it. This will separate the electrodes 8 and draw an are between them. The

by the dash pot 16. The arc thus drawn is given a substantially horizontal shape or is even bowed downward by the magnet 12 carried at the lower end of the member 10.

When the member 10 is moved upward in the manner hereinbefore described, the clutch 20 which is normally locked to it by the spring 22 moves with it until the pawl 21 ther upward movement of the member 10 will take place without corresponding movement of the clutch 2O. As soon as the member 10 begins to descend, however, the clutch 20 wi again be locked to the member 10. The downward movement of'the member 10 is checked by the engagement of the awl 21 with thestop 24. It will thus be 0 served that the length of arc struck after each feeding operation is governed by the play of the pawl 21 between the stops 23 and 24. At each feeding operation of the lamp, the member 10 is pulled through the yoke 19 of the armature 16 thus produced, will cause the contacts 44 and 45, whereupon the coils 17 will be denpvgfiized. When this occurs, the

ed to a suitable source of current, current electrodes 8, conductor 63, winding of the speed at which the arc is drawn is regulated engages the upper stop 23, after which fur-v raised from the position shown in the drawing. When by. reason of increase of arc length resulting from consumption of the electrodes, or from other cause, the voltage of the arc risesabove a predetermined amount, the current flow through the coil 35 becomes sufficient to attract the armature 36, thus bringing about engagement between the contacts '37 and 38. This throws a low resistance shunt comprising the conductor 69, contacts 37 and 38 and conductor 68, about the winding 42, thus rendering the cutout device inoperative and allowing the contact 44 to move into engagement with the contact 45. When this occurs, the coils 17 are again energized and the electrodes 8 are moved together, after which an arc of the predetermined length is again struck. This feeding operation is repeated as often as is necessary to compensate for the consumptionof the electrodes by the arc.

Asthe electrodes 8 consume in the operation of the lamp, the are between their lower ends moves upward toward the platform 2. By properly proportioning and arranging the bell-crank levers 26 the magnet 12 is moved toward the platform 2 as rapidly as the arc approaches the platform, thus preserving unchanged the properrelative position of the arc between the electrodes and magnet 12. The under surface of the magnet 12 may be arranged to form a reflector for throwing'the light of the arc'downward, or if desired an auxiliary reflector may be carried by the member '10 as-shown in Fig. 4.v It will be obvious to all those skilled in the art that the mechanism which I have herein described and illustrated is but one of many forms in which my invention may be embodied, and that many variations may be made from the form shown without departing from the spirit of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. Inan arc lamp, a pair of electrodes inclined to the horizontal, means for producing an are between the ends of saidelectrodes, means for moving the electrodes horizontally to compensate for the material consumed by the arc, a magnet for'deflecting the are be v tween said electrodes, and means for moving the magnet vertically to compensate for the change in position of the are as the electrodes are consumed.

2. In an arc lamp, a air of cooperating electrodes between which an arc 1s maintained, feeding mechanism for moving the electrodes to compensate for their consumption by the arc, a magnet for normally maintaining the arc deflected, and means for automatically moving the magnet to comensate for the change in position of the are between the electrodes resulting from the consumption of the electrodes by the arc. 3. In an arc lamp, a pair of electrodes between which an arc is maintained, means for normally maintaining the arc deflected, and means for automatically changing the position of the arc deflecting means to compensate for the change in position of the are resulting from the consumption of the electrodes.

4. In an arc lamp, a pair' of electrodes between which an arc is maintained, a magnet the poles of which are on opposite sides of said are for normally maintaining the arc deflected, and automatic means for feeding said electrodes to compensate for their consumption and for changing theposition of the magnet in response to a change in the position ofthe arc resulting fromthe electrode consumption.

- 5. In an arc lamp, electrodes, feeding mechanism for moving the electrodes to compensate for their consumption, magnetic means for normally maintaining the are deflected, and a connection between, said magnetic means and said feeding mechanism whereby the magnetic means is automatically moved to compensate for the change in. position of the arc resulting from the consumption of the electrodes:

6. In an arc lamp, a pair of electrodes arranged out of alinement with each other and between which an arc is maintained, feeding mechanism for moving the electrode to compensate for the consumption by the are, a magnet for normally maintaining the arc deflected from its natural position, and means for automatically moving the magnet to com ensate for the change of position of the are etween the electrodes resulting from the consumption of the electrodes by the arc.

In witness whereof I havehereunto set my hand this 14th day of September, 1904.

GEORGE W. CRAVENS. Witnesses:

BENJAMIN B. HULL, HELEN ORFoRn. 

